CexV1−xO2 (x: 0, 0.25–1) nanocomposites as efficient catalysts for degradation of 2,4 dichlorophenol

Abstract

Composite oxides of CexV1−xO2 (x: 0, 0.25–1) were synthesized, characterized and applied for removal of 2,4-dichlorophenol. The catalysts were prepared by co-precipitation method and characterized by X-ray diffraction (XRD), Transmission electron microscopy (TEM), N2 adsorption at −196°C, Fourier transform Infra Red (FT-IR) and Fourier Transform Raman (FT-Raman) techniques. The X-ray diffractograms of Ce –V oxide powders with different Ce/V molar ratios revealed the coexistence of CeO2 with a tetragonal CeVO4 and orthorhombic V2O5 phase. The Brunauer–Emmet–Teller (BET) surface areas and pore volumes of synthesised composites were in the range of 26.21–1.26m2/g and 0.01–0.0007cm3/g respectively. FT-Infra Red and FT-Raman measurements confirmed the formation of different mixed oxides. Effects of Ce-V ratio, H2O2 dose, reaction temperature, and 2,4-dichlorophenol (2,4-DCP) concentration on CWPO of 2,4-DCP were investigated in detail. CexV1−xO2 were effective catalysts for wet peroxide oxidation of 2,4-DCP and the highest catalytic activity was obtained using the Ce0.5V0.5O2 catalyst with complete 2,4-DCP degradation at 60min, and at 180min COD and TOC removal percentage was 84% and 41.03% respectively. Atomic Absorption Spectrometry (AAS) indicated the extent of leaching of vanadium to be negligible. The mixed oxides were reusable and stable on consecutive use as indicated by XRD and surface area measurements.